The MPTCP is a Transmission Control Protocol (TCP) enhancement technology put forward by the Internet Engineering Task Force (IETF). The MPTCP is intended to allow multiple member transmission paths to be used in one TCP connection to transmit load of user equipment (UE), that is, a service data flow, so as to maximize utilization of a transmission resource and improve a redundant backup of the transmission resource.
Currently, the MPTCP has been applied in an application scenario in which a wireless local area network (WLAN), such as Wireless Fidelity (WiFi), and a cellular mobile network, such as 3rd-Generation (3G) or 4th-Generation (4G) interoperate with each other to ensure quality of service of communication. For example, when handing over between a WiFi network and a 4G network, user equipment uses the MPTCP to perform load control to maintain service continuity, so as to ensure service experience of a user; and the MPTCP is used to perform load sharing on a service flow of same user equipment between the WiFi network and the 4G network to ensure that the service flow of the user equipment reaches load balance between member paths of each network, so as to ensure communication transmission efficiency of each network.
In an application scenario in which multiple networks cooperate to perform multipath transmission, how to perform load control by using the MPTCP to provide good service experience for a user becomes a technical problem that needs to be urgently resolved by a communication operator. Generally, a solution provided in the prior art is to distribute load of user equipment to a network access point with a lower congestion (load) level only according to a congestion control principle, so as to improve the communication transmission efficiency.
However, in the foregoing method, only a congestion level of each member transmission path of the TCP is used as a condition for determining load distribution. Therefore, a cause of congestion that occurs on each member transmission path cannot further be determined, and a specific instruction of load distribution cannot be delivered to a congested member transmission path according to the cause. Consequently, in a scenario in which load of each member transmission path is shared, service experience of a user deteriorates.